State officials and activists are calling on the city to do a deeper investigation into the possibility that enslaved African Americans were buried at a site on the border of Park Slope and Gowanus.

Currently a vacant lot located adjacent to an American Legion hall at the intersection of Third Avenue and Ninth Street, the site is being eyed by the city for a new prekindergarten.

Since 2015, state legislators have been fighting to preserve the site. It’s long been rumored it is the burial ground of 256 members of the Maryland Heroes, a group of Revolutionary War soldiers who died in battle on August 27, 1776.

It wasn’t until recently that local historians discovered the lot may also hold the remains of slaves from the 19th century.

“The area has long been believed to be a possible burial ground for the Maryland Heroes who fought in the historic battle of Brooklyn, and recent evidence suggests that in addition to these men, it is likely that enslaved persons were also buried at this site,” Assemblywoman Jo Anne Simon said last week.

The diary of Adriance Van Brunt could be the key. Van Brunt was a member of a prominent 19th century slave-holding family, and his diary suggests the location was a burial ground.

“We must not desecrate this burial ground,” State Senator Jesse Hamilton said. “We must respect and protect those who have given their lives for this country and those who have served as slaves in this country.”

Local activist Bertha Lewis criticized the administration for potentially glossing over the city’s slave history.

“New York was the financial capital of the slave trade, and Brooklyn’s population was once 30 percent enslaved,” she said. “We have a choice. Are we going to gloss over over this history by building a school on top of the bodies of enslaved African Americans, or are we going to give this the thorough investigation is deserves?”

Toya Holness, a spokesperson from the Department of Education, said that a thorough investigation of the site, which started in June, is still underway.

“The SCA will continue to engage all appropriate entities and stakeholders throughout this process,” she added.

Activists are skeptical however of the city-hired surveying firm AKRF Inc. In 2007, the company produced a report claiming that there was not sufficient evidence to support preservation of houses on Duffield Street in Downtown Brooklyn that may have been part of the Underground Railroad.

Shawne’ Lee, director of 227 Abolitionist Place Museum Heritage Center, said the company ignored recommendations that supported the preservation of the buildings.

“We do not believe the company has the capacity or motivation to properly research Brooklyn’s connection to slavery,” she said.